Decorative lamp



FIG. 1 is a right-front perspective view of the decorative lamp showing our new design.

FIG. 2 is a right side elevation view thereof.

FIG. 3 is a front side elevation view thereof.

FIG. 4 is a left elevation view thereof.

FIG. 5 is a rear elevation view thereof.

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken line disclosure represents portions of the decorative lamp which form no part of the claimed design. 

CLAIM The ornamental design for a decorative lamp, as shown and described. 